Theoretically, this should enhance training adaptations in athletes. However, most studies show little benefit of HMB supplementation in athletes. A 2004 study by Hoffman [435] found HMB supplementation to be ineffective in collegiate football players after short term supplementation. It has been hypothesized that HMB will delay or prevent muscle damage; however this has limited evidence as suggested in previous sections. There are a few studies that have been positive [115]. A 2009 study found that HMB supplementation did positively affect strength in trained men [436]. While HMB supplementation may still have some scientific rationale there is little evidence that is can directly affect

performance in moderately trained subjects. Glycerol Ingesting glycerol with water has been reported to increase fluid retention [437]. Theoretically, PKA activator this should help athletes prevent dehydration during prolonged learn more exercise and improve performance particularly if they are susceptible to dehydration. Although studies indicate that glycerol can significantly

enhance body fluid, results are mixed on whether it can improve exercise capacity [69, 438–443]. Little research has been done on glycerol in the last five years however, a 2006 study agreed with previous findings in that glycerol has little impact on performance [444]. Too Early to Tell A number of supplements purported to enhance Megestrol Acetate performance www.selleckchem.com/products/cftrinh-172.html and/or training adaptation fall under this category. This includes the weight gain and weight loss supplements listed in Table 3 as well as the following supplements not previously described in this category. Medium Chain Triglycerides (MCT) MCT’s are shorter chain fatty acids that can easily enter the mitochondria of the cell and be converted to energy through fat metabolism [445]. Studies are mixed as to whether MCT’s can serve as an effective source of

fat during exercise metabolism and/or improve exercise performance [445–449]. A 2001 study found that 60 g/day of MCT oil for two weeks was not sufficient at improving performance [450]. In fact Goedecke found that not only did MCT supplementation not improve performance, but, actually negatively affected sprint performance in trained cyclists [451]. These findings have been confirmed by others that MCT oils are not sufficient to induce positive training adaptations and may cause gastric distress [452, 453]. It must be noted that while most studies have not been favourable, one 2009 study found that MCT oil may positively affect RPE and lactate clearance [454]. It does not appear likely that MCT can positively affect training adaptations, but further research is needed. Apparently Ineffective Glutamine As described above, glutamine has been shown to influence protein synthesis and help maintain the immune system.